Key parameters at a glance

A radius of 2.68 Earth radii
A mass of 7.65 Earth masses
Surface gravity around 1.07 g
An orbital period of 7.053 days
Semi-major axis 0.0692 AU
Distance from Earth 592.78 light-years
Earth Similarity Index 0.679
Travel time at Voyager 1 speed 10,453,595 years

2 siblings around K2-58

K2-58 b shares its host star with 2 other confirmed planets. Side-by-side measurements below.

Planet	Type	Radius (R⊕)	Mass (M⊕)	Period (d)	Eq. T (K)	Year
K2-58 c	Super-Earth	1.62	3.26	2.537	—	2016
K2-58 b this	Sub-Neptune	2.68	7.65	7.053	—	2016
K2-58 d	Super-Earth	1.71	3.57	22.883	—	2016

K2-58 b Planet Profile

Physical Specs

Radius

2.68 R⊕

Radius (Jupiter)

0.239 R♃

Mass

7.65 M⊕

Mass (Jupiter)

0.024 M♃

Density

2.18 g/cm³

Surface Gravity

1.07 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.679

HZ Position Inner

Controversial No

Discovery

Year 2016

Method Transit

Facility K2

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#896of 1978

top 45.2%

This planet

2.68R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-487 c 2.68 R⊕ Kepler-1184 b 2.68 R⊕ Kepler-899 b 2.68 R⊕

Metric	Earth	K2-58 b	Jupiter
Radius (R⊕)	1.00	2.68	11.21
Mass (M⊕)	1.00	7.65	317.83
Density (g/cm³)	5.51	2.18	1.33
Surface Gravity (g)	1.00	1.07	2.53
Insolation (S⊕)	1.00	118.00	0.037

Star Catalogue Identifiers

TIC

TIC 437703489

Gaia DR2

Gaia DR2 2599975224481836672

Gaia DR3

Gaia DR3 2599975224481836672

System

K2-58

Percentile among Sub-Neptune cohort

Radius 2.680 R⊕ · percentile 54 / cohort 1978

Mass 7.650 M⊕ · percentile 50 / cohort 1978

Orbital period 7.05 d · percentile 22 / cohort 1946

Distance 181.75 pc · percentile 28 / cohort 1975

ESI 0.679 · percentile 91 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

7.053 days

Semi-major axis

0.0692 AU

Eccentricity

—

Inclination

88.85 °

Year Length

A year here lasts approximately 7.05 Earth days (1.9% of a terrestrial year) at a mean orbital distance of 0.0692 AU.

Transit Fingerprint

Depth

0.103 %

Duration

1.899 h

Impact parameter b

0.530

Rp / R★

0.028000

Transit midpoint (BJD)

2,456,986.9763

Photometric dip

Transit produces a flux drop of 1,030 ppm lasting ≈ 1.90 h.

Extended Orbital Architecture

Planet / star radius ratio

0.028000

Semi-major axis / stellar radius

23.900

Impact parameter (b)

0.530

Transit mid-time (BJD)

2,456,986.9763

Angular separation (arcsec)

0.38100

Eq. Temperature

—

Insolation (S⊕)

118.00

Earth = 1.00

Earth Similarity (ESI)

0.679

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Crossfield et al. 2016

Instrument

Kepler CCD Array

Publication

2016-09

Observation locale

Space

Discovery cohort

Planets confirmed in 2016 at K2 (12 shown).

K2-72 d · Rocky Terrestrial K2-72 b · Rocky Terrestrial K2-91 b · Rocky Terrestrial K2-72 c · Rocky Terrestrial K2-102 b · Super-Earth K2-90 c · Super-Earth K2-72 e · Super-Earth K2-83 b · Rocky Terrestrial K2-88 b · Rocky Terrestrial K2-80 c · Super-Earth K2-83 c · Super-Earth K2-65 b · Super-Earth

Host System: K2-58

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,413 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.860 R☉

Stellar Mass

0.890 M☉

Metallicity [Fe/H]

0.11

Extended Stellar Properties

Surface gravity (log g)

4.522 dex

Stellar density

2.009 g/cm³

Systemic radial velocity

6.49 km/s

Metallicity ratio

[Fe/H]

Distance

181.75 parsec

Light-years 592.78 ly

V-band magnitude

12.42 mag

Voyager-speed travel 10,453,595 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

5.474 mas

Total Proper Motion

11.969 mas/yr

PM Right Ascension

4.80 mas/yr

PM Declination

-10.97 mas/yr

Galactic Cartesian (pc)

x = 0.871 · y = -0.428 · z = -0.243

Equatorial (J2000)

RA 333.82184° · Dec -14.04986°

Galactic ℓ, b

44.721° · -51.380°

Ecliptic λ, β

330.663° · -3.009°

HTM-20 index

-679001174